In other words, 491 miligrams is 0.00000023 times the weight of a Rhinoceros, and the weight of a Rhinoceros is 4,300,000 times that amount.

(for Black rhinoceros, Diceros bicornis) (Adult, male)An adult black rhinoceros weighs between 2,100,000,000 miligrams. Rhinoceros are extremely aggressive — nearly one of every two males will die as a result of fighting with other rhinoceros.

In other words, 491 miligrams is 0.00000018 times the weight of The Tongue of a Blue Whale, and the weight of The Tongue of a Blue Whale is 5,600,000 times that amount.

(Balaenoptera musculus) (adult)The tongue of a Blue Whale can weigh up to 2,700,000,000 miligrams. Despite their tremendous size, blue whales feed almost exclusively on tiny crustaceans called krill and cannot swallow anything much larger than a beach ball.

In other words, 491 miligrams is 0.000000131 times the weight of a Hippopotamus, and the weight of a Hippopotamus is 7,630,000 times that amount.

(Hippopotamus amphibius) (adult, male)The average weight of an adult male hippopotamus ranges from 3,750,000,000 miligrams. Appearances to the contrary, adult hippos cannot swim or float in water; they actually move by leaping and walking across lake bottoms at about 8 kph (5 mph).